Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual é a matrícula no Delaware Valley College?
 ###Tabelas: CREATE TABLE siena_college_research_institute_survey (siena_college_research_institute_survey_id AUTO_INCREMENT PRIMARY KEY, Seq. VARCHAR, Name VARCHAR, Background INT, Party Leadership INT, Communication Ability INT, Relations with Congress INT, Court Appointments INT, Handling of Economy INT, Luck INT, Ability to Compromise INT, Willing to take Risks INT, Executive Appointments INT, Overall Ability INT, Imagination INT, Domestic Accomplishments INT, Integrity INT, Executive Ability INT, Foreign Policy Accomplishments INT, Leadership Ability INT, Intelligence INT, Avoid Crucial Mistakes INT, Expert's View INT, Overall INT) CREATE TABLE freedom_conference (freedom_conference_id AUTO_INCREMENT PRIMARY KEY, Institution VARCHAR, Location VARCHAR, Nickname VARCHAR, Founded INT, Type VARCHAR, Enrollment INT, Joined MAC INT) CREATE TABLE division_one_final_table (division_one_final_table_id AUTO_INCREMENT PRIMARY KEY, Position INT, Team VARCHAR, Played INT, Drawn INT, Lost INT, Goals For INT, Goals Against INT, Goal Difference VARCHAR, Points 1 VARCHAR) CREATE TABLE pregnancies (pregnancies_id AUTO_INCREMENT PRIMARY KEY, Congresswoman VARCHAR, State VARCHAR, Date of delivery VARCHAR, Mother's age INT, Baby gender VARCHAR) CREATE TABLE stanley_cup_finals (stanley_cup_finals_id AUTO_INCREMENT PRIMARY KEY, Date VARCHAR, Visitor VARCHAR, Score VARCHAR, Home VARCHAR, Record VARCHAR)  
SELECT MAX Joined MAC FROM freedom_conference WHERE Institution = Delaware Valley College